BLACKSBURG, Virginia (CNN) -- A year and a half before before Cho Seung-Hui went on a deadly shooting spree on the campus of Virginia Tech, a professor was so concerned about his anger that she took him out of another teacher's creative writing class and taught him one-on-one.

The former chairwoman of Virginia Tech's English department, Lucinda Roy, said the anger Cho expressed was palpable if not explicit.

"It was like something out of a nightmare," MacFarlane wrote in a blog. "The plays had really twisted, macabre violence that used weapons I wouldn't have even thought of.

"Before Cho got to class that day, we students were talking to each other with serious worry about whether he could be a school shooter."

Cho paid $571 for a 9 mm Glock 19 pistol just over a month ago, the owner of Roanoke Firearms told CNN Tuesday. He also used a .22-caliber Walther pistol in the attack, police said. (Interactive: The weapons used in the shootings)

John Markell said Cho was very low-key when he purchased the Glock and 50 rounds of ammunition with a credit card in an "unremarkable" purchase.

Shooter's note

However, ABC News reported that other law enforcement sources said Cho did leave some kind of note in his dorm room. It contained an explanation of his actions and states, "You caused me to do this," ABC News reported.

Authorities are still investigating whether Cho had any accomplices in planning or executing Monday's rampage, Flaherty said.

Cho, a resident alien from South Korea, lived at the university's Harper Hall, Flinchum said.

"He was a loner, and we're having difficulty finding information about him," said Larry Hincker, associate vice president for university relations.

Governor not ready to talk gun control

Tuesday, after an emotional convocation service on campus attended by President Bush, Virginia Gov. Tim Kaine announced that at the university's request, he was appointing an independent panel to review Monday's tragedy.

"It is a very important thing, and a standard thing, that a thorough after-action review be done, both on the event and the response, so that we can learn all we can about them."

However, Kaine said he wasn't interested in arguments about gun control.

"To those who want to try to make this into some little crusade, I say: Take that elsewhere. Let this community deal with grieving individuals and be sensitive to those needs."

As questions continued to arise about how police reacted to the first shooting at the dorm,university President CharlesSteger on Tuesday defended the response, saying police believed it to be "a domestic fight, perhaps a murder-suicide" that was contained to one dorm room.

Police cordoned off the 895-student West Ambler Johnston dorm and all residents were told about the shooting as police looked for witnesses, Steger said.

Authorities were still investigating what they believed was an "isolated incident" when the slaughter started at Norris Hall.